Download Extinction

Extinction
Extinction of species is a recent discovery
Cuvier’s “Ohio animal”
http://en.wikipedia.org/wiki/Georges_Cuvier
tive anatomy, Georges
calls it a mammoth,
an elephant
Cuvier
• Georges Cuvier, anatomist and naturalist
at the Museum of Natural History, Paris,
used comparative anatomy to prove that
fossil bones belonged to a species
(American Mammoth) that no longer
existed
29
(1769-1832)
oved that fossils of mammoths were
t from all living elephant species
an elephant
Cuvier’s “Ohio animal”
“Ohio Animal”
30
Mammoth vs. Indian elephant
lower jaw vs. Indian Elephant
used comparative anatomy, calls it a mammoth, an elephant
29
Extinction is ‘normal’
• >99% of all species that have ever existed are now extinct
• Extinction rates have varied quite a bit through time
• Different groups have different characteristic species
durations:
Mammals: ~ 2 million years
Foraminifera: ~ 20 million years
Marine Animal Extinction rates
over the past 540 million years
•
Late Ordovician
•
Permian-Triassic
•
Pleistocene-Recent
?
Potential drivers of extinction
Background
Mass
• Competition
• Rapid climate change
• Predation
• Sea level change
• Habitat loss
• Wholesale habitat loss
• Disease
• Ocean acidification
• Climate change
• Anoxia/hypoxia
• Bad luck
• Bolide Impacts
• Disease?
Selectivity of extinction:
What traits might influence extinction risk
under different scenarios?
Individual
•
•
•
•
•
•
•
Physiology
Thermal tolerance
Diet
Home range size
Reproduction
Gestation period
etc.
Population
•
•
•
•
•
•
•
Geographic range
Latitudinal range
Environmental range
Population density
Population growth rate
Dispersal
etc.
Selective signature of mass extinctions: what is unusual
about extinctions relative to extinctions at other times?
(0(!# &"12$3$4-( #"
7978:;<=
#+( 0'3.% 3(&@&-'!?
(&#'0( (,,(&# ", 23(A
'! 79D8:E< ,"3 56
%#((2C .!'!#(33.2#()
#+ $?( '! 789; F!!H
#'"! $# #+$# #'1( +$)
-($%# $% ,$3 4$&K $%
#@ 3$#( ,"3 79JE:J8
23"#(&#'"! ", $!@
+( *(--AK!"*! LLMNN
8 '% %"1(*+$# 1"3(
B&(%% 1"3#$-'#@ *$%
#(% 4('!? +'?+(%# ,"3
$!) #+"%( $?() !8<
&"!%'%#(!# *'#+ $!
".!? $).-#% F!H #+$!
#+3".?+ 23(A(B'%#'!?
1"3#$-'#@ 2$##(3!%
#() #*'&( '! #+( 2$%#
J#4%&,#72 ) K(5&' 5,$D$%(#. 5,K('(0,-
An analogy: age distribution of mortality
!"#$ %$ 1,203' 45"/ 6#,&/"#(2 2#- (#4%&,#72 (# 89) (# 035,,
during a:2-260,‘normal’
pandemic
<<=> -202
(#4%&,#72 62#-,/($'
45"/flu
12&,5
; 9,54%(#. :vs.
4"5 ?@AB 4"5 C2''2$3&',00'
"#%D=
during the
1918 pandemic
Dowdle, 1999, Bulletin of the WHO
The Late Ordovician
Mass Extinction
http://www.lifeonthinice.org/index.php#mi=2&pt=1&pi=10000&s=0&p=8&a=0&at=0
Climate change & mass extinctions
class
Archaeocyatha
Bivalvia
Cret.-Pg.
L. Ord
Perm.-Tri.
L. Dev
2000
Brachiopoda
Cephalopoda
Conodonta
Crinoidea
Demospongea
Echinoidea
Gastropoda
Graptolithina
Gymnolaemata
Tri.-Jur.
Number of genera
of marine animals
Extant genera
3000
Ostracoda
Rugosa
Scleractinia
Stenolaemata
Stromatoporoidea
1000
Tabulata
Trilobita
z.other
other
climate
1
Warm
0
-1
-2
0
-3
Cm
500
O
S
D
400
C
P
T
300
200
Millions of years before present
J
Millions of years before present
K
100
Pg
Ng
Cool
0
biocomplexity and biodiversity began in the Early
Trotter et al., 2008, Science
Marine invertebrate genera
The Late Ordovician
Mass Extinction
Fig. 1. Biodiversity patterns of marine fauna
through geological time.
Middle Cambrian to Silurian (except Pridoli) tax2000
onomic diversity trends
at genus level [modified
from Sepkoski (15)]. In1600
set shows Phanerozoic
taxonomic diversity of
marine faunas at fam1200
ily level [modified from
Sepkoski (12)]. Cambrian:
M, Middle; U, Upper.
800
Ordovician T, Tremadoc;
Ar, Arenig; Ln, Llanvirn;
C, Caradoc; As, Ashgill.
400
Silurian: Lly, Llandovery;
W, Wenlock; Lw, Ludlow.
Carboniferous conodonts have nonetheless yielded
www.sciencemag.org
SCIENCE
VOL 321
syste
there
(Fig
cono
equiv
et al
Islan
Gotla
incre
equi
(d18O
vide
clim
clim
Early
glob
to m
~25
mod
the M
temp
ing t
and
ature
25 JULY 20
•
~60% of marine genera disappear during the Katian (457- 445.6 mya)
and Hirnantian (445.6 - 443.7 mya) stages
•
Two pulses: end-Katian pulse coinciding with cooling & expansion of
Gondwanan ice sheets, end-Hirnantian pulse coinciding with warming
& contraction of ice sheets
•
No clear selective signature with respect to which taxonomic groups
go extinct
The Late Ordovician globe
Very limited life on land, High CO2 , Low O2
Siberia
Laurentia
Baltica
Go
ndw
a
ana
n
a
w
d
n
o
G
modified after R. Blakey: http://jan.ucc.nau.edu/~rcb7/450moll.jpg
The Ordovician Period: little or no animal life
on land, but abundant marine life
Who was hit by the extinction?
Trilobites
http://weekstrilobites.com/Flexicalymene.htm
Mollusks
http://www.fossilsforsale.com/site_arc/index.cfm?
action=item&prod_id=191&
Brachiopods
http://drydredgers.org/brachplaty.htm
Tabulate and
Rugose Corals
http://louisvillefossils.blogspot.com/2012/12/
naming-fossils.html
Graptolites
Crinoids
http://www.geo-logic.org/Palaeontology/Graptolites.htm
http://louisvillefossils.blogspot.com/2010/12/
agaricocrinus-americanus-crinoid.html
Who was hit by the extinction?
http://www.palaeocast.com/episode-2-isotelus-rex/#.UXHCgaUgF20
Ultimate cause: glaciation and subsequent
deglaciation of south polar Gondwana
?
Late Ordovician glacial deposits in Morocco
Le Heron et al., 2010, Sedimentary Geology
What caused cooling? Some ideas:
May have been caused by movement
of Gondwana over the south pole...
Siberia
Laurentia
Baltica
Go
ndw
a
ana
n
a
w
d
n
o
G
modified after R. Blakey: http://jan.ucc.nau.edu/~rcb7/450moll.jpg
Or, increased chemical weathering of silicate rock
due to Taconic mountain-building
The silicate weathering feedback:
modified after R. Blakey: http://jan.ucc.nau.edu/~rcb7/450moll.jpg
http://images.summitpost.org/original/499686.jpg
Or, increased chemical weathering of continental
silicate rocks by early terrestrial ecosystems
Late Ordovician moss and fungal spores
The silicate weathering feedback:
http://www.shef.ac.uk/content/1/c6/03/41/74/
wellman-research-pic-dec-07.jpg
Science. 2000 Sep 15;289(5486):1884-5.
Late Ordovician North America (Laurentia)
Anticosti
Island
modified after R. Blakey: http://jan.ucc.nau.edu/~rcb7/450moll.jpg
Baie des Homards
Silurian
Point Laframboise
Ordovician
49°15'N
49°30'N
49°45'N
English Head
Natiscotec Creek
Salmon River
LEGEND
Chicotte
Jupiter
Gun River
Merrimack
Becscie
Ellis Bay
Vauréal
measured
section
64°30'
64°00'
Figure 1
Macaire Creek
Lousy Cove
Fox Pt.
0 5 10
20
kilometers
63°30'
63°00'
62°30'
62°00'
Vauréal Canyon
Gun River Fm.
1 cm.
Ellis Bay Fm.
1 cm.
Becscie Fm.
Vauréal Fm.
Stratigraphic ranges of orthide
brachiopods on Anticosti
Laframboise Mbr.,
Ellis Bay Fm.
Jin and Zhan, 2008
Western Anticosti:
Pt. Laframboise
Shallow-water
deposits
Deep-water
deposits
Western Anticosti: Pt. Laframboise
Deep water deposit
s (Silurian)
Reefs
CaCO3 shells
record the
chemistry of the
water in which
they grew...
Korte et al., 2005
Stable isotope ratios in fossil shells
-Isotopes of an element vary in number
of neutrons, but have a fixed number of
protons and electrons
-Isotopes have identical chemical
interactions, but are often sorted by mass
δ13C : ratio of 13C to12C, provides information
about changes in carbon cycle
δ18O : ratio of 18O to16O, provides information
about changes in climate
in the other sectors, and they are considerably
smaller (Fig. 6B).
15
10
Lousy Cove
Height in section (m)
tions D804 and 901 (Laframboise Point) in the
western sector is characterized by 1 m of interbedded grainstones and lime mudstones (Figs.
4B, 4C, and 4D) that appear in some places
to internger with the Laframboise Member
bioherms (Fig. 4D). Some grainstones display
hummocky cross-stratication or wave ripples.
A few meters up-section, the grainstone beds
become thinner and less common, and mudstone dominates.
In the east-central sector, the Becscie Formation begins with thin resistant sandstone
that overlies the Laframboise oncolite platform
bed where bioherms are absent (Fig. 5D). The
sandstone frequently displays low-angle crossstratication. Above the sandstone, the Fox
Point Member typically becomes recessive and
poorly exposed for 2 to 4 m. At section 911, on
the right bank of the Salmon River, across from
the upstream section (9 Mile Pool), bioherms of
the Laframboise Member are directly overlain
20
Laframboise
Pt. Laframboise:
Fox Point Member (Becscie Formation)
13
18
C,
δ
O
δ
The base of the Becscie Formation at sec-
Fox Point
Jones et al., 2011
5
0
–5 –4 –3 –2 –1 0 1 2 3 4 5 –30
δ18Ocarb, δ13Ccarb (‰, VPDB)
–28
–2
δ13Corg (‰
in the other sectors, and they are considerably
smaller (Fig. 6B).
Jones et al., 2011
15
10
Lousy Cove
Height in section (m)
western sector is characterized by 1 m of interbedded grainstones and lime mudstones (Figs.
4B, 4C, and 4D) that appear in some places
to internger with the Laframboise Member
bioherms (Fig. 4D). Some grainstones display
hummocky cross-stratication or wave ripples.
A few
up-section,
the productivity
grainstone beds
Enhanced
upwelling,
• meters
become and
thinner
and carbon
less common,
organic
burial? and mudstone dominates.
In
east-centralorganic
sector, carbon
the Becscie For• theDecreased
mation oxidation
begins with
thin resistant sandstone
rate?
that overlies the Laframboise oncolite platform
bed•where
bioherms of
areexposed
absent (Fig. 5D). The
Weathering
sandstone
frequentlyrocks?
displays low-angle crosscarbonate
stratication. Above the sandstone, the Fox
Point Member typically becomes recessive and
poorly exposed for 2 to 4 m. At section 911, on
the right bank of the Salmon River, across from
the upstream section (9 Mile Pool), bioherms of
the Laframboise Member are directly overlain
20
Laframboise
is controlled
Fox Point Member (Becscie Formation)
by global organic
The base of the Becscie Formation at seccarbon
burial
tions D804
and 901 (Laframboise
Point) in the
Fox Point
13
δ C
5
0
–5 –4 –3 –2 –1 0 1 2 3 4 5 –30
δ18Ocarb, δ13Ccarb (‰, VPDB)
–28
–2
δ13Corg (‰
in the other sectors, and they are considerably
smaller (Fig. 6B).
15
10
Lousy Cove
Height in section (m)
western sector is characterized by 1 m of interbedded grainstones and lime mudstones (Figs.
4B, 4C, and 4D) that appear in some places
to internger with the Laframboise Member
bioherms (Fig. 4D). Some grainstones display
hummocky cross-stratication or wave ripples.
A few
up-section,
the grainstone
Increased
glaciation
of the beds
• meters
become thinner and less common, and mudpoles?
stone dominates.
In the east-central sector, the Becscie Forof the
mation
begins with
thin tropics?
resistant sandstone
• Cooling
that overlies the Laframboise oncolite platform
bed where bioherms are absent (Fig. 5D). The
Both?
•
sandstone frequently displays low-angle crossstratication. Above the sandstone, the Fox
Point Member typically becomes recessive and
poorly exposed for 2 to 4 m. At section 911, on
the right bank of the Salmon River, across from
the upstream section (9 Mile Pool), bioherms of
the Laframboise Member are directly overlain
20
Laframboise
18O is controlled by
δ
Fox Point Member (Becscie Formation)
both local temperature
The base of the Becscie Formation at secand global ice volume
tions D804 and 901 (Laframboise Point) in the
Fox Point
Jones et al., 2011
5
0
–5 –4 –3 –2 –1 0 1 2 3 4 5 –30
δ18Ocarb, δ13Ccarb (‰, VPDB)
–28
–2
δ13Corg (‰
Hirn.
SILURIAN
Brachiopod
18
δ O trends from
Rhuddanian
Aeronian
Trilobite
Rugose coral
-1
! Ocalcite
18
Brachiopod
Anticosti
-3
Cinci. Arch
-4
U. Miss. V.
-5
Trilobite
Rugose coral
Bryozoan
Anticosti
Cinci. Arch
U. Miss. V.
Bryozoan
-2
Temperature,
T !18Ocalcite °C
!18Oseawater °CTemperature,
nian
Temperature and seawater
“clumped” isotope paleothermometry
ORDOVICIAN
Katian
455
38
-1
36
-2
34
-3
32
-4
30
-5
28
383
362
34
1
32
300
-1
28
ORDOVICIAN
Katian
450
Hirn.
445
SILURIAN
Rhuddanian Aeronian
18Owater
Age, δ
mya
Results:
440
Brachiopod
Trilobite
Rugose coral
Bryozoan
Anticosti
Cinci. Arch
U. Miss. V.
455
455
450
450
445
445
440
440
450
450
445
445
440
440
Age, mya
LGM
Ice-free
455
455
Age, mya
Finnegan et al., 2011, Science
Results: Inferred Ice Volumes*
*Assuming mean δ18Oice equivalent to Last Glacial Maximum
Ice volume, 106 km3
ORDOVICIAN
Katian
Hirn.
SILURIAN
Rhuddanian Aeronian
150
100
50
Last Glacial Maximum
Present
0
455
Present
450
Age, mya
445
440
LGM
Ordovician-Silurian boundary sections
Atypical: Anticosti Island
Typical: Kentucky
n
a
i
n
a
d
d
Rhu il.)
S
(E.
)
.
d
r
O
.
an (L
i
nt
Hirna
Katian (L
. Ord.)
Rhuddanian (E. Sil.)
Katian (L. Ord.)
Build-up of glaciers on land drains shallow marine habitats
San Francisco Bay 18,000 years ago
Image courtesy Lynn Ingram
Sedimentary rocks record changes in
continental flooding through time
Late Ordovician-Early Silurian sedimentary
rocks and fossil collections in Laurentia
•
Gap-bound sedimentary packages from Macrostrat (Peters, 2005)
•
Fossil occurrences from PBDB (Alroy et al, 2008)
Whiterock
Chazyan
Blackriveran Kirkfield
Shermanian Maysvillian
Richmondian
Hirnantian
Rhuddanian
Aeronian
Telychian
Wenlock
Fig. 1. Maps
of sedimentary rocks deposited
across Laurentia from Middle Ordovician
Mixed carbonate-clastic
Chert (Dapingian) through the Early Silurian (Wenlockian) time. Red points
Sandstone
mark PaleoDB collections. Colored polygons indicate sedimentary rock distribution and lithotype. Blue ¼ carbonate, dark blue ¼ mixed carbonate-clastic,
gray ¼ fine clastics, tan ¼ mixed clastics,
yellow ¼ sand, orange ¼ coarse clastics, blue-green ¼ chert, pink ¼ evaporites, brown ¼ metamorphic indet.,
Carbonate
Mixed clastic
dark green ¼ igneous indet. Only the uppermost unit in each column is plotted.
Fine clastic
Evaporite
Finnegan et al., 2012, PNAS
l
nvil
yas
n
ia
Draining of shallow tropical seaways
nn
nn
tidaia
Koan
te m
laich
R
Shallow
ocean
ttiiaa
aann
rirnn
HHi
Hirnantian
late Katian
Exposed
land
Salt
basin
ckk
llooc
eenn
WW
Open
ocean
0°
0°
l
nvil
yas
n
ia
Draining of shallow tropical seaways
nn
nn
tidaia
Koan
te m
laich
R
Shallow
ocean
ttiiaa
aann
rirnn
HHi
Hirnantian
late Katian
Exposed
land
Salt
basin
0°
ckk
llooc
eenn
WW
Open
ocean
0°
Hypothesis: genera that had large areas of their Late
Ordovician geographic ranges drained should have
experienced exceptionally high extinction rates
Ranges reflect interaction of climate and geography
40
north
30
20
10
0
Mean sea surface temperature
300
500
700
Bivalve species
rank.orderlatitudinal ranges
900
Changing temperatures would have imposed additional
stresses on genera with limited thermal tolerance
Modeled Late Ordovician sea surface temperatures
Before glaciation
During glaciation
394
A.D. Herrmann et al. / Palaeogeography, Palaeoclima
Modified from Herrmann et al., 2004, P3
Fig. 6. Annual mean sea surface temperature distribution for simulations with high sea level, Ashgill pa
Caradoc paleogeography, and pCO2 levels of (c) 8 ! , and (d) 15 ! PAL; low sea level, Ashgill paleo
Changing temperatures would have imposed additional
stresses on genera with limited thermal tolerance
Modeled Late Ordovician sea surface temperatures
Before glaciation
During glaciation
394
A.D. Herrmann et al. / Palaeogeography, Palaeoclima
Modified from Herrmann et al., 2004, P3
Fig. 6. Annual mean sea surface temperature distribution for simulations with high sea level, Ashgill pa
Caradoc paleogeography, and pCO2 levels of (c) 8 ! , and (d) 15 ! PAL; low sea level, Ashgill paleo
Hypothesis: genera with narrow latitudinal ranges should
have experienced exceptionally high extinction rates
Determinants of marine invertebrate extinction risk
B
C
Polar Ice Volume
Tropical Temperature
% Habitat Loss
C
D
D
Finnegan et al.,
2012, PNAS
Ae ¼ Aeronian, Tely ¼ Telychian, Wen ¼ Wenlockian. Hirnantian and Rhuddanian intervals contain too few genera for analyzing some pre
Selective Signature:
80
%
Extinction
Extinction
%%Extinction
Exclusively lowlatitude genera
much harder hit
than those with
broad latitudinal
distributions
Dapingian-early
Katian
Before mass extinction
late
Katian
Mass
extinction
Rhuddanian-Wenlockian
After mass extinction
60
Finnegan et al.,
2012, PNAS
40
20
0
20
30
40
50
60
70
80
Maximum
Paleolatitude
Maximum
paleolatitude
90
Mean Temperature (°C)
Fig. S4. Proportional extinction of genera as a function of maximum paleolatitude of occurrence for the late Katian interval compared to the a
Dapingian and early Katian (Middle-Late Ordovician) and Rhuddanian to Wenlockian (Early Silurian). Error bars are 95% binomial confidenc
largely reflect variation in the number of genera in each bin.
Finnegan et al. www.pnas.org/cgi/doi/10.1073/pnas.1117039109
Vandenbrouke
et al., 2010
Conclusions:
• The Late Ordovician glaciation was at least as large, in
terms of ice volumes, as the Pleistocene glaciation
• Tropical seawater temperatures fell by ~5º C during the
Late Ordovician glacial maximum
• Growth of glaciers caused sea levels to fall and drove a
massive reduction in the area of shallow seaways
• Reduction of shallow seaways combined with cooling
temperatures led to large-scale habitat loss and
resulting extinction
Why did Late Ordovician glaciation cause a major
mass extinction, but not subsequent glaciations?
Late Ordovician
Sea level, continental
configuration &
biogeography
Mio-Pliocene
R. Blakey: http://jan.ucc.nau.edu